This reference design is a 4.2-W, single-channel, automotive 12-V battery input flyback bias supply for IGBT/SiC isolated gate drivers. The supply accepts a wide input range of 4.5-V to 65-V DC. The output is configurable as +15 V,–8 V or +20 V, –4 V at loads up to 180 mA for driving the IGBT/SiC MOSFET power modules. The system consists of reverse polarity protection, electric transients clamping, and overvoltage and undervoltage protection circuits. The flyback controller implements primary-side regulation with better than ±1% load and line regulation performance. The power stage design includes the dual-channel isolated gate drivers with 5.7-kVRMS reinforced isolation and designed in compact form factor of 100 mm × 62 mm. It includes isolated DC bus sensing, isolated temp sensing, logic shoot-through protection and diagnostic features.
Features
- Wide-VIN flyback converter over the input voltage of 4.5-V to 65-V DC
- Protection for clamping high voltage conducted transients to safe levels for downstream circuitry
- Programmable overvoltage and undervoltage protection on supply output
- Primary side regulation with no optocoupler for extended life time and small form factor
- Power stage design includes dual channel isolated gate driver, DC bus sensing, and temp sensing for high voltage testing